The invention relates to a method for ion beam processing of the surface of a substrate in which the substrate is positioned relative to an ion beam that is generated by an ion beam source, and the known property pattern of the surface of the substrate is partially processed by the ion beam with a defined action pattern such that a new technologically defined property pattern of the surface is formed. The invention furthermore relates to an apparatus for performing the above mentioned method.
Property patterns of the surface of a substrate should be construed to mean all physical and chemical properties, as well as the surface topography, relative to defined surface area regions of the surface of a substrate. The action pattern of the ion beam contains the local ion current density distributions, with corresponding ion energy distribution, relative to defined surface area regions of the substrate that the ions of an ion beam act upon.
In accordance with the prior art, methods and devices are known in which an ion beam with constant beam characteristics is moved at a variable speed relative to the surface of a substrate that is to be processed. Beam characteristics include ion acceleration, ion energy distribution, ion current density, and ion density distribution of the ion beam ion. Also known, is the use of diaphragms between the ion beam source and the substrate.
Processing of the surface topography of a substrate is especially important, particularly for many aspects of micro- and nano-technologies. From targeted production of adjustable stratum thicknesses by thinning strata in thin film technology, to targeted removal of individual layers of atoms to nano-profiling of “high-grade” surfaces, all of these increasingly require the use of ion beams as a working tool.
In addition to geometrically modifying surface topography in the context of removing or coating, local modification of the properties of the surface is also important for micro- and nano-technologies. Thus, influencing the properties of the deposited stratum is known during ion beam-supported deposition methods when ions strike at the same time during the coating. Thus, for example, the density of the deposited stratum can be varied or the growth of the stratum can be changed from amorphous to crystalline, or the stoichiometry of the stratum can even be affected.
Targeted modification of surfaces using ion bombardment thereof is also possible. In this case, only the break-up of functional groups on the surface of plastic materials, for example, for modifying adhesive properties, and adding foreign atoms, e.g. for surface hardening, is cited.
DE 198 14 760 A1 describes, for example, a method for ion beam processing of solid surfaces with a beam having a rectangular cross-section. The ion beam source, controlled by a computer at a pre-specified starting angle, is guided over the workpiece surface with translatory movements of fixed or variable distance with variations in speed depending on the position, ion beam parameters, and material properties.
The object of the invention is to provide a method for ion beam machining of surfaces of the type cited in the foregoing, with which high efficacy is attained and with which technical complexity is low. The object is furthermore to provide a device for performing such method.